1. Field of the Invention
The present invention generally relates to an improvement in a toggle linkage for use in a closure panel detachably arranged in an opening formed in a vehicle roof.
2. Description of the Related Art
It is well known to provide a vehicle roof having an opening which is defined by a roof frame and is opened and closed by a metal or glass closure panel for ventilating purposes. The conventional closure panel is hingedly mounted to the roof frame and is moved between a ventilating position and a closed position by means of a manually operated toggle linkage.
An exemplary toggle linkage of this type is disclosed in Japanese patent publication No. 58/45937. Such toggle linkage generally comprises a first link pivotably connected by pivot pins to brackets on the lower surface of a closure panel, a handle integral with the first link, a bearing component fixedly mounted on the lower surface of a vehicle roof, and a pair of second links connecting the handle with the bearing component. Each of the second links includes a sleeve and a pivot pin. The second links are interconnected by a pin with its opposite ends inserted into the respective sleeves. Further, springs are disposed within the sleeves to normally urge the second links in a direction away from each other, thereby ensuring connection of the handle with the bearing component. With this arrangement, the closure panel is tilted upwardly to a ventilating position by rotating the handle in a clockwise direction, and can be detached from the vehicle roof by moving the second links in a direction closer to each other against the action of the springs to separate the pivot pins from the bearing component. It is important to note that in situation where external loads are applied to the vehicle with the closure panel in its angularly raised ventilating position, the handle is further rotated and the closure panel is moved rearwards. As a result, the forward portion of the closure panel is undesirably separated from the roof frame. In order to prevent this situation, it is necessary to improve the stiffness of a hinge mechanism or a vehicle roof assembly. This results in an undesirable increase in the weight and costs of the vehicle.